As communication technology advances, evolution of 3G mobile communication systems is about to reach their fourth generation (4G). Such a 4G mobile communication system enables portable terminals capable of using mobile communication systems to be based on IP (Internet Protocol) in communication, and implement fast upload and download speeds.
Evolution for reaching the 4G mobile communication system contributes to sending/receiving user data even faster. On the contrary, portable terminals are expected to consume more power to cause the available time of portable terminals to be reduced.
Accordingly, there is a need for developing a method for improving battery life on portable terminals in line with emerging 4G mobile communication systems.
The exemplary Green-T(echnology) of EUREKA project has studied the technology for minimizing power consumed by the 4G portable terminals by adopting the heterogeneous radio access technology in order to overcome the aforementioned energy trap thereof.
In particular, the Green-T project aims to develop a method for implementing data communication by using a neighboring short-range wireless communication system if much transmission power is required for sending/receiving data to/from a base station because terminals are far away from the base station.
For example, FIG. 1 shows an exemplary system block using a wireless LAN or wireless PAN (Personal Area Network) for a portable terminal with battery limitation in short-range wireless communication with another portable terminal while the other portable terminal uses 4G mobile communication for relay to a base station.
The aforementioned another portable terminal may be a portable terminal free from power consumption compared with the portable terminal in the battery limitation.
FIG. 2 shows a system block for sending/receiving data to/from a portable terminal by using a short-range wireless communication system, for example, a wireless LAN or high-speed wireless PAN, not 4G mobile communications.
The aforementioned FIGS. 1 and 2 illustrate reducing power consumption by utilizing a neighboring portable terminal or neighboring short-range wireless communication system while adopting short-range wireless communication, not direct wireless communication through a base station.
Portable terminals of which the battery levels drop below a certain level and which do not consume enough power or have battery limitation utilize short-range wireless communication systems, for example, a wireless LAN or wireless PAN in place of using a base station in order to reduce power consumption, as shown in FIGS. 1 and 2. In this case, however, unnecessarily more power than required is consumed, and even more power may be required than using a base station.
For example, radio data packets used in a short-range wireless communication system are sent/received through a specified carrier frequency. A portable terminal receiving them determines whether the destination of the received radio data packets is the portable terminal itself at the link layer (for example, at the MAC (Media Access Control) layer) which is one of the seven layers of the OSI (Open Systems Interconnection) model and then carries out subsequent processing.
This process involves various processes. For example, the physical layer receives radio signals and demodulates the received radio signals, and the MAC layer then determines the MAC data packets to determine a destination address by using the packets.
A portable terminal having a limited battery or power level may know a destination address only through this process, which consumes even more power. Furthermore, this is even worsened in the case that a plurality of terminals are connected in a short-range wireless communication system the portable terminal wants to access.
Therefore, there is a need for a method for receiving radio packets through short-range wireless communication, a portable terminal and a short-range wireless communication system by filtering out a plurality of unnecessarily radio data packets to reduce power consumption even though the portable terminal uses a short-range wireless communication system as an alternative to a mobile communication system in which the portable terminal uses a base station.
Meanwhile, a portable terminal may not use a 4G mobile communication system. For example, the portable terminal may use a 3G mobile communication system or other mobile communication system, and further access the Internet through short-range wireless communication. There is also a need for a method for receiving radio packets through short-range wireless communication, a portable terminal and a short-range wireless communication system to reduce power consumed to access a short-range wireless communication system by the portable terminal.